Radiographic apparatus



Aug 24, 19 43. V .A. J. KIZAUR RADIOGRAPHIC APPARATUS Filed June 22, 1942 5 Sheets-Sheet 1 art/w J INVENTOR.-

RADIOGRAPHIC APPARATUS Filed June 22, 1942 s'sheets-sheet 2 RN @N INVENTORi-w 5 m?) F Q mm Rw Q R H a w/ r d. H mu V t w c I 3 C w Q R. NW m m Aug. 24, 1943. A. J. KIZAUR RADIOGRAPHIC APPARATUS Filed June 22, 1942 5 Sheets-Sheet 3 INYENTORF- JrZ/zanf 1Z2 Aug. 24, 1943; A. J. KIZAUR RADIOGRAPHIG APPARATUS Filed June 22, 1942 5 Sheets-Sheet 4 INYENTOR. A (Zri/zwnlffi aar;

Aug. 24, 1943. A. JLIKIZAUR 2,327,603

RADIOGRAPHIC APPARATUS Filed June 22, 1942 5 Sheets-Sheet 5 Patented Aug. 24, 1943 UNETED STA'E'EIS PATENT OFFH CE 7 2,327,603 RADIOGRAPHIO APPARATUS Arthur J. Kizaur, Cicero, Il].,.assignor to General Electric X-Ray Corporation, v Chicago, EL, a

corporation" of New York 7 Application June22, 1942, Serial No. 447,957

12 Claims. (or 250-66) The present invention relates in general'to plate changers and has more particular reference to plate supporting and shifting mechanism for use in radiography, that is to say, the making of X-ray pictures on sheets or plates sensitive to X-rays.

An important object of the invention is to provide neat and compact apparatus for support ing sensitive material in position for exposure to X-rays for the making of X-ray photographs, and for shifting the supported material successively to a number of predetermined exposure positions; a further object being to provideplate shifting apparatus which'will" accomplish the shit ting operation rapidly and substantially Without vibration or jar; a still further object being to provide apparatus of thechar'acter mentioned which is of simple construction and light in weight whereby the same may be readily supported, as over a diagnostic table, and easily manipulated and shifted thereby facilitating the positioning of the apparatus in the making of X-ray photographs. l v

Another important object is to provide apparatus for progressively shifting a plate of sensitive photographic material successively to a number of predetermined relatively displaced exposure positions comprising a plate shifting cycle.

Another important object is to provide mechanism selectively adjustable for shifting a plate in accordance with a desired one ofa number of different plate shifting cycles; a further object being to provide an apparatus which may be adjusted to present a plate in fixed position for exposure or to present the plate successively for exposure in two exposure positions, or to present the plate successively in a plurality of relatively shifted exposure positions l Another important object is. to provide mechanism operable to presenta plate successively in a plurality of exposure positions whereby teen; able several adjacent plate portions to be suc cessively exposed in order to produce several related pictures upon adjacent portions of the same plate. I

Another important object is to provide apparatus for successively projecting a plate carrier from retracted position into position for exposure, the apparatus being self adjusting to successively present different portions of a plate in the holder in position to be exposed whereby'several portions of the supported plate may be successively exposed as the plate holder is successively projected from retracted position.

Another important object resides in utilizing the reciprocatingmovement of the holder for the purpose of actuating tripping devices adapted progressivelyto condition the device to present the plate successively for exposure in relatively shifted or offset positions.

Anotherimportant object is to provide a simplified control for plate shifting mechanism whereby the same may be readily conditioned for the presentation of a plate in any desired one of a number of diilerent plate changing cycles; a further object being to utilize progressively shiftable. stop means for determining the position at :Which the plate-is presented bythe projecting movement of a plate carrier.

Another important object is to provide for displacing a plate carrier in a direction normal to. the direction of plate projecting movement of' the carrier; a'furtherobject being to utilize sefor projecting a plate carrier simultaneously in a plurality of directions in combination with selectively operable means for limiting the movement in each direction whereby toselectively' determine-the projected position of the plate; a further object being to progressively actuate the limiting means in order to alter the projected position or" the plate carrier; 2. still further object being to actuate the stops selectively whereby the plate carrier may successivelybe presented in a plurality of positions forming a plate shifting 5 cycle; a still further object being to provide a master control whereby the limiting stops may be conditioned to control the mechanism for operation in accordance with any one of a number of plate changing cycles.

Another important object is to provide a plate carrier reciprocable in a predetermined path between retracted and projected position, in combination with motor driven means and selectively conditionable stops for determining the project ing movement of the plate carrier and for dis more fully understood from the following description which, taken in connection with the accompanying drawings, discloses a preferred embodiment of the invention.

Referring to the drawings:

Figure 1 is a face view of plate changing apparatus embodying the present invention;

Figures 2 and 3, respectively, are sectional views taken substantially along the lines 2-2 and 3-4 in Figure 1;

Figure 4 is an enlarged View of a portion of the apparatus shown in Figure 1;

Figure 5 is a perspective view of parts, including selectively operable control means for controlling operation of the apparatus;

Figures 6, 7 and 8 are sectional views taken along the line 6-4 in Figure 4 showing control switches forming a part of the control means in position for accomplishing four, two and single position operating cycles; and

Figures 9, 10 and 11 are diagrammatic'views showing the control means positioned for accomplishing, respectively,four-position; two-position and single position operating cycles;

To illustrate the invention, I have shown on the drawings plate shifting mechanism particularly adapted for presenting a sheet or plate of sensitive material in position for exposure to X-rays for the purpose of making X-ray photographs.

It is frequently desirable, in making X-ray photographs for diagnostic purposes, to make exposures by successively placing plates in the same positionwith respect to the patient and exposing the plates to X-rays emanating from a source of X-rays, In order to accomplish the foregoing purpose, it is highly desirable to provide means for quickly presenting sensitive material successively in accurately aligned position for exposure, and particularly when dealing with a restless patient is speed and accuracy desirable. It will be appreciated, also, that the plate shifting operation desirably should be accomplished substantially without jar to eliminate the possibility of misaligning the sensitive material. Since X-ray photographs are frequently required of injured persons, frequently not in any condition to cooperate in the picture making, it is desirable to provide lightweight apparatus adapted for convenient mounting, as on or over a diagnostic table, and it is also desirable to provide apparatus in form-capable of easy adjustment to the patient.

The apparatus of the present invention embodies a frame and mechanism of lightweight construction adapted for easy application to a patient and containing mechanism for serially positioning light sensitive material in the same relative position with respect to the patient whereby to facilitate the making of a series of X-ray pictures by successively exposing the material to the action of X-rays emanating from a source of X-rays.

The plate shifting mechanism or serialographic apparatus H, as shown in the drawings, comprises a frame preferably formed as a pair of cooperating shell-like housings l3 and I5 suitably secured together to provide a relatively fiat box-like enclosure or housing l6 for plate shifting mechanism IT. The casing portion l3 comprises the front of the device and is formed on one side with a window opening I9 in which is mounted aremovable frame 2| secured in place as by means of the latch 22 on one side and suitable hinges or other fastening means at the other. This frame carries a fluorescent screen 23 comprising a panel of material adapted to become luminescent when exposed to X-rays in "preferably comprising a sheet metal frame havagainst the object to be photographed, the device being positioned with the panel 23 opposite the portions to be photographed. The X-ray source is then positioned at a suitable distance on the side of the object being photo-graphed remote from the plate changing device I I so that rays from the source may pass through the object and then impinge upon the screen 23. If desired, the screen may be etched with centering lines to enable the device II to be accurately positioned with respect to the object by means of a preliminary X-ray examination and the shadow thereby cast upon the screen 23.

The plate shifting apparatus ll comprises carriage means 25 supported in the housing I5 for movement longitudinally thereof upon guide rails 27 preferably mounted on the housing portion 13 along the upper and lower edges thereof. The rails 21 preferably comprise metal strips fastened as by screws on pedestals 29 formedon'the' frame I 3. The carriage means 25 comprises a plate 3| secured at its opposite edges on mount-, ing straps 33 which carry grooved roller wheels.

35 adapted to engage the edges of the strips forming the rails 21 whereby the plate 3| may be moved in the housing lfi'from a retracted position on one side of the window-opening I 9 to pro-,,

jected position within said opening, the carriage means 25 being shown in retracted position in;

Figure 1 of the drawings.

The plate 3| carries a pair of parallel spaced tudinal plate projecting movement of the carriage means on the rails 21. A plate holder 4| ing upper and lower flanged edges 43 for slidably receiving the upper and lower edges of a plate container or cassette 45 is carried on the rods 31 for sliding movement therealong, the plate holdtioned in the holder 4| when the carriage means 25 is in the retracted position illustrated in Figure 1 by opening the screen carrying frame 2| and passing the cassette throughthe opening I9 and theneeinserting it edgewise into the carrier 1 25, the upper and lower flanges of which are fitted with spring means 49 for yieldingly securing the cassette in place in the holder, stop pins 5| for limiting the insertion of the cassette,-and

latch lugs 53 which, in combination with the springs 49, serve to retain the cassette in mounted position.

It should be understood that X-rays from'the source may be confined to impinge upon a re-' stricted area within the confines of the window l9, thereby defining an exposure position, by ad-,

justing the position of the source and by adjusting suitable diaphragm means associated with the source.

The carrier 25, together with the mechanism thereon, may be manually shifted from retracted position into position for exposure opposite the,

window l9, and means are provided for serially or successively altering the position at which the plate is presented opposite the opening IS in tion.

order thusto enable adjacent portions of the material inthe cassette to-be presentedin position forexposure by successively presenting the plate carrier in various relatively shifted positions withinlthe exposure area represented by the-opening l9. 7 l

Tothis end, the carriage means 25 is fitted with a handle 55 which projects outwardly of the casing member l3 througha slot 51 in thechousing, so that, by manipulating the handle 55, the carriage means 25 maybe reciprocated in the housing it between retracted and projected positions, In order to shift the sensitive material on the carriage means and thus allow it to be presented at various elevations in the opening it, I provide, suitably mounted on the carriage means 25, an electric motor 59 which issupported on the plate 3i by means of a suitable bracket in position below the carrier 25, This motor; through a train of gears and a selectively operable clutch,

drives a gear El which is journaled on the plate 35. The gear ti has an arm 63 secured thereon and extending radially therefrom. The end of the arm 83 is pivotally connected to one end of a connecting .rod 65, the other end of which is pivotally connected as at 6'! to a bracket 69 on the plate holder 4i so that by turning the gear 6! through one-half revolution from the position shown in Figure .1 the plate holder may be projected upwardly through a distance equal to twice the length of the arm The arm 63, it will be noted, is approximately equal in length to one-quarter of the effective length of the sensitive material in the cassette so that the total displacement of the material between i the lower and upper limits of movement of the holder M is one-half the effective length of the sensitive material between its, upper and lower,

edges. By selectively controlling the clutch connection between the motor 59 and the gear M I may position either the upper half or the lower half of the sensitive material in the cassette at a definite elevation in the carriagev and, of course, I may similarly locate any intermediate portion of the sensitive material at said definite eleva- In the present embodiment of my invention the apparatus is arranged to position the upper half of the light sensitive material at an elevation midway between theupper and lower edges of the opening is when the holder li is in the position shown inFigure l, and to position the lower half of the sensitive material in the same position midway between the upper and lower edges of the opening iii when the holder i-l is at the upper limit of movement on the carriage means 25.

By moving the carriage means into position opposite the opening it, I may make a picture on the upper half of the light sensitive material when the holder ii is at the elevation shown inFigure 1 and then merely by elevating the holder H I may immediately make a second picture on the lower half of the sensitive material This may be accomplished, of course, by suitably shielding the lower and upper portions of the light sensitive material when making these successive exposures. Likewise, by utilizing selective stops for limiting the movement of the carriage means 25 in a longitudinal direction I may successively expose each quarter section of the sensitive material bysuc cessively positioning each quarter section in the same exposure position.

The entire area of the light sensitive material may, of course, be exposedl if desired, whenever the, holder ,6! isprojected into position in the and solenoid 85. p The stop means 13 comprises a turnable detent opening opening l9. Consequently, the illustrated ap'' paratus may be used either to expose the entire.

matically shifted as a result of successive recipe rocations of the carriage means 25 between projected and retracted position whereby to present the several portions of the plate in position to be exposed, I provide selectively operable stop means H inthe frame H in position to selectively engage cooperating stop means it supported on the carriage means 25, the stop means lsbeing supported in position to engage the stop means H during the projecting movement of the carriage means 25 and thereby stop the carriagemeans and the plate holder ll when the plate has reached a desired position within the The stop means I! comprises an element l2 pivoted as at T5 and having a pair of arms formed with upstanding lugs H and i9.

The element i2 is provided with an arm 8i whereby it may be turned on its pivot '15, the

arm 8i being normally urged as by means of a spring 83 into position presenting the lug it in place for cooperative engagement with stop means 13. The arm'Sl is also connected with a solenoid 85 which when energized serves to turn the element 12 against the influence of the spring 83. to present the lug ii in position to cooperate with the stop means 13. Suitable pins 18 or equivalent stop means may be provided tolimit the turning movement of the element 72 in either direction under the influence oi the spring 33 turn has geared connection with the motor 59 through selectively operable mechanism 99; which is under the control of the knob 55.. By manipue lating the knob 55 the control mechanism 89 may be conditioned to turn the detent 81 so that as the carriage means issuccessively projected the detent 81 may selectively engage the stop lug 19 or may pass said stop means. It will be noted that the lug 19 projects above the top of the lug H, The configuration of the detent 6'! is such that it may not. at any time engage the lug l! but it cooperates selectively only with the lug 19.

The frame 9i includes a projection it)! which dement of the detent 81 with the lug l9, or it may be stopped in either of the positions determined by the engagement of the projection ill! with either of thelugs ll and 79. The cooperating stop means Hand 73 thusprovide for the stoppage of the carriage means and the holder ll in threeadjacent relatively shifted positions within the opening l9, and the parts are arranged so that the holder ll may be stopped in a medial position Withinthe opening l9 and in ofiset positions on opposite ides of the medial position and displaced from said medial position a distance equal to one-half the effective width of the lightsensitive plate which the holder is adapted to mount. It will be apparent that by correlating the operation of the co-operating stop means H and I3 with the means determining the position of the holder II on the rails 31, the carrier may be successively presented in the opening I9 in position with the several sections of a sensitive plate therein presented successively in a predetermined exposure position. To this end, theselectively operable means 99 comprises atrain of gears conmeeting the motor 59 with a gear element I95 mounted for free turning movement on a shaft I01 between spring pressed clutch members I03 keyed on the shaft on opposite sides of the gear element I05, whereby the shaft III'I may be driven through friction clutch means comprising the element I 05 and the clutch members I08.

The shaft It! carries a :pinion "39 which, through an idler gear I I I, drives the carrier elevating gear 6| and the selector cam driving gears 95 and 91. The shaft III? also carries a selectively operable circular stop plate II3 having an edge notch H5 adapted to receive one or other of a plurality of locking detents for holding the shaft against rotation in predetermined angular positions. In the illustrated embodiment, there are two detents I I! and I I9 disposed on diametrically opposite sides of the axis of the shaft to lock it against turning in two positions relatively displaced by 180. The detents are spring urged to press upon the periphery of the plate and are thus adapted to fall into the notch II5 when in registration therewith. When locked by the detent H9, the haft I! is in position such that the holder II is either atits maximum or at its minimum elevation on the carriage means 25, and when the shaft is locked by the detent III, the holder is in position midway between the upper and lower limits of its vertical movement.

The handle 55 is mounted for limited turning movement 'on the carriage, being conveniently journaled on the projecting end of the shaft I01 which, of course, is free to turn with respect to the handle. The handle, however, as shown in Figures 6, '7 and 8, may be turned to and secured in any selected one of three positions, representing the three operating cycles which the device shown is adapted to perform, namely, the four, the two, and the single position cycles, respectively, illustrated in Figures 6, '7 and 8. Fastened to the handle is a detent control cam I2I, and when the handle 55 is positioned to condition the apparatus for the performance of the two and four position cycles of operation, the cam I2I blocks the detent II'I from entering the slot H5, while leaving the detent II9 free to latch in the notch II each time the shaft I0! turns through 180. When the handle is set to condition the apparatus for ingle position operation, the cam l2I blocks the detent I I9 and leaves thedetent I II free to operate.

The motor 59 and the solenoid 85 are controlled through an electrical circuit system energized.

from a suitable electrical power source I23 including switches which, in turn, are controlled by the handle 55 and the detents II! and H9. Power from the source I23 is delivered to a pair of bus bars I22 mounted on insulated supports in the casing I3 adjacent the edge of the carriage means 25, which carries wiping contacts I24 in position to engage the bars I22, whereby to energiz'e the electrical system on the movable carriage. Another bar I26 and wiping contact I28 connects the electrical system on the carriage with the stationary solenoid on the frame I3.

The control system comprises a'solenoid control circuit I25 comprising a normally openswitch' I27 in series with the solenoidbetween the power source. The switch I21 is closed to energize the solenoid and draw the stop 11 into active position whenever the handle is in position'to condition the apparatus for either the one or the two position operation, the switch being open to' allow the stop I9 to be active during four posi-' tion operation.

The motor is controlled by a circuit comprising four normally open switches I30, I3 I, I32 and I33 arranged in series connected pairs, the switchpair I30 and I3I being connected in parallel reof the detents III and I I9, being open only when the corresponding detent is in the notch I I5,and closed whenever the detent is out of the notch,

whether riding on the edge of the disk or held" out by the cam I2I.

The switches ISI and I33 are normally open but are closed by operation of cam means I36 on the handle'55, the switch I3I being closed only when the handle is set for one position opera tion of the apparatus and open otherwise, While the switch IE3 is closed for two and four position operation and open for single position operation. The switch I2! is also controlled by the.

cam means I 36 so as to be open for the four position cycle andclosed for the one and two position cycles.

The switches may be mounted on the frame of the carriage 25 in driving relation with the detents Ill and III and with the cams I2] and I35, the switches I21, I3I and I33 being preferably arranged as a stack I33 in position to cooperate with the cam means I36.

Operation When the control handle 55 is set for one position operation, as shown in Figure 8, the carriage 25 being in retracted position shown in Figure 1, the switch I3I will be in closed position, the

switch I33 being open so long as the handle 55 remains in the setting for one position operation. The switch I30, however, will be closed if the detent I I! is not in latched position in the notch I I5. As the handle is turned to the setting shown in Figure 8, the cam I2I will raise the detent IIB from the disc H3 to render the detent II9 inactive so long as the handle remains in such setting. Should the detent H9 be latched in the notch when the handle is set for one position,

operation, it will be released from the notch by the cam; and if the detent II! is supported'on the edge of the disc H3 when the handle is turned to its setting, the motor will be. energized through the closed switches I39 and I3I until it shall have turned the shaft Iill into position permitting the detent II! to latch in the notch.

the solenoid is energized to present the stop] member I! in operative position to engage the stop lug IllI on the carriage frame 25, wherebyto limit longitudinal movement of the frame-to a position in which the plate holder is centered in the window I9. Consequently, by merely pushing upon the handle to move the carriage 25 into the window I8, the sensitive material in the holder M may be accurately placed in the mid exposure position shown at MI in Figure 5. After exposure of the material in such mid position, the

I carriage may be retracted by pushing on the handle 55, an unexposed plate may be mounted in the holder and the carriage again advanced by pushing on the handle 55 to place the unexposed plate-in the same midexposure position I I I. The

apparatus thusmay be operated without change of adjustment to present plates for exposure in the mid position where the plates or any portion thereof may be exposed. I

If it be desired to expose the upper and lower the handle isturned to the setting shown in Figures 6 or '7, the cam I2I will raise the detent II'I from the disk H3 torender the detent H1 inactive so long as the handle remains in "such settings. notch II5 when the handle isshiited to either the two or four position settings, the detent II! will be releasedfrom the notch by the cam HI; and if the detent H9 is supported on the edge of the disk H3 when the handle 'is turned to either setting, the motor 'will be energized through the closed switches I32 and I 33 until it shall have turned the shaft Iill into position permitting the detent H9 to latch in the notch H5, whereupon Should the detent Ill be latched in the the switch I32 will open, the motor 59 will'stop,

and the shaft Iill' will be latched in position with the plate carrier either at the uppermost or lowermost limit of its vertical movement on the carriage 25'.

When the handle is in the two position setting shown in Figure '7, the solenoid switch [21 will be closed to energize the solenoid and thus present the stop member TI inoperative position to engage the stop lug Iill on the carriage frame 25 and thus limit the longitudinalmovement of the frame to a position in-which the plate holder is centered in the window I9; as is the case when the apparatus is set for one position operation. Consequently, by merely pushing upon the handle to move the carriage 25'into the window space I9, the sensitive material in the holder 4| may be accurately centered in the'- window. Since the detent H9, however, is latched in the notch H5, the holder will be either at the upper 'or lower limitof its vertical travel on the carriage and consequently the plate will be presented in either the lower or upper medial positionshown at I42 and I42 in Figure 5, and it willbe seen that the lower half of the plate in the upper position I42 occupies the same medial exposure position I43 occupied by the upper half of the plate in the lower position I42. After exposure of .one-hali of'the plate in the said medial exposure position I43, the carriage 25 may be moved. to theretracted position shown inFigure 1- bypushing on the handle and'immediately returned to projected position determinedfby "the stops 11 During the retraction, and projection, and preferably during the retracting movement,

the detent I I9 is engaged by a tripping finger I35 and released from the notch IE5. The tripping finger I35 may comprise a spring actuated lug pivoted on the housing in position to engage the detent H9 during the longitudinal movement of the carriage 25 on the tracks 21, and as shown, it is arranged to release the detent H9 as the carriage is retracted from projected position in the window It, the trip finger depressing against the influence of its spring to permit the detent H9 to ride freely over the finger during projecting movement of, the carriage'25 toward the window. I

By releasing the detent H9 during retractive carriage movement, the shaft IIl'I will be released and the switch I32 will be closed to energize the motor, which will turn the shaft through one revolution before the detent I I9 may relatch inthe notch H5, the detent III being held inactive by the cam I2 I One revolution of the shaft I EI'I turns the gear BI through 180 ofrotation, thus moving the. plate holder from the down position I42 to the up position I42, or vioeversa, so that when the holderagain reaches the projected po sition determined by thestops TI and HM, the unexposed half will be in the medial exposure position .I43ipreviously. occupied by the other half of the plate during exposure thereof. The unexposed: half may then be exposed andvthe plate removed from the holder for, development by retracting the carriage-andremoving the plate in its cassette from the holder All. The apparatus, thusmay be operated Without change of adjustment to present the upper andlower portions ofthe plates successivelyin the medial ex- ,posure position I43.

When the handle 55 is in the four position :setting shown in Figure 6, the apparatus is set to successively position the quarter sections of a plate in an exposure station disposed atthe center of the window I9. In'such four position setting, the solenoid switch I2"I is released by the handle and assumes open position so that the solenoid is de energized and the stopmember 'I'Bis brought into active position by the spring 83', the stop T'I being moved out .of active position As is the case when set for two position operation, the apparatus,; when set for four position operation, functions to present the holder I-I in the opening I9. in either fully raised or fully lowered position when the carriage 25 is projected by pushing o'nlthe handle. The segmental stop 81 has such geared connection with the shaft IO'I that it will turn through one complete rotation While the shaft IIl'I" turns four times and the gearEI turns twice. Thesegmontal stop 87 is adapted to engage the stop it during two successive carriage projections and then to ride over the stop I9- -to present the plate in shifted position for a second exposure. During retraction, the release finger 535 will disengage the detent H9 and cause the motorto turn the shaft it! through one complete turn, thus moving the holder 4| to raised position, and turning the segmental stop through 90 of rotation. V

The second projection of the carriage will be stopped by the engagement of the members 19 and 87 in offset position with the plate in position shown at M l in Figure 5, the lower left hand quarter of the plate being in the centered exposure position M5. After exposure of such centered plate quadrant, the carriage may again be retracted and immediately re-projected to present the plate in shifted'position for a third exposure. During retraction, the release, finger ifiiwilldisengage the detent H9 and cause the motor to turn the shaft lG'i through one complete turn, thus moving the holder M to lowered position and turning the segmental stop through 90 of rotation.

The third projection of the carriage will be stopped by the engagement of the members 79 and mi, since the segmental stop member has been turned to an inactive position and over-rides the stop member 19. The plate will thus be presented in the window i9 in the offset position shown at Main Figure 5, with the upper righthand quarter of the plate in the centered ex,- posure position Hi5. After exposure of suchlcentered plate quadrant, the carriage may 1 again be retracted. and immediately re-projected to present the plate in shifted position for a fourth exposure. During retraction, the release finger I35 disengages the detent H9 and causes the motor to turn the shaft it? through one complete turn, thus moving the holder il to raised position and turning the segmental stop through 90 of rotation.

The fourth projection of the carriage will thus be stopped by the engagement of the members 19 and. liil, the segmental stop being inactive and over-riding the stop 59' so that-the plate will be presented in the offset position shown at MS in Figure 5, with its lower right-hand quarter in the centered exposure position M5. After exposure of such centered plate quadrant, the carriage may be retracted to complete the operating cycle, the release finger 35, during final retraction, again tripping the detent! 19 to allow the motor to lower the holder and to advance the segmental stop 81 through 90 of rotation into active position for engagement with the stop 19. At the conclusion of the four position operating cycle, the exposed plate, in its cassette, may be removed from the holder and replaced with an unexposed plate, the apparatus being ready to repeat its operating cycle.

As a refinement, the shaft 89 which carries the segmental stop may be geared to an index wheel I 49, having its rim projecting through a slot in the housing and marked at 90 intervals with the numerals 1, 2, 3 and-4 to indicate the progressive condition of the apparatus in the performance of its four position cycle of operation. This index wheel also functions to indicate progress during two position operation and shows fixed positions for one position operation. By noting the wheel and always starting the four position cycle with the index wheel at the initial index position, the condition of the apparatus will be known at all times, and the exposure sequence will be identical in each" exposed plate. Likewise, by starting the two cycle operation always with the index wheel showing either the first or third index position, the .operatingsequence will be known at all times and.

identical exposure sequence will be had in all ex-. posed plates. 7 a

It is thought thatthe invention and its numerous attendant advantages will be fully understood from the foregoing description, and it is obvious that numerous'changes may be made in the form, construction and arrangementof the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the form herein disclosed being a preferred embodiment for the purpose of illustrating the invention. I 1

The invention is hereby claimed as follows:. 1. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the workstation to provide a working cycle, said frame means and "carriage means comprising.

carriage reaches a position in its path determined by said shiftable stop and to by-pass said cooperating stop to allow. thecarriage means to be stopped in adifferent position. i

' 2. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the Work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, and cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movement of the carriage means in any one of several relatively shifted positions at the work station. to present a plate on said carriage means in a desired position at said station, said stop mechanism comprising a stop member and an adjustably shiftable stop on one of said relatively movable structures,jsaid shiftable stop being positionable selectivelyto engage a cooperating stop on the other structure when the carriage reaches a posh tion in its path determined by said shifta'ble stop and to by -pass said cooperating stop to allow the carriage means to be'stopped in ,a different position by the engagement of said stop member with the cooperating stop.

3. Plate positioning mechanism comprising frame means forming a workstation, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively" movable structures, cooperating stop mechanism on the carriage means and on said plate on said carriage means in a desired position I at said station, said stop mechanism comprising an adjustably shiftable stop on one of saidrela tively movable structures, said shiftable stop be.- ing positionable selectively to engage a cooperating stop on the other structure when the carriage reaches a position in its path determined by said shiftable stop'and to by-pass said. cooperating tively operable to halt movement of the carriage means in any one of several relatively shifted positions at the work station to present a plate on said carriage means in a desired position at said station,. and progressively operable means to adjust the selectively operable stop mechanism during successive working cycles of i the carriage means. 1

5. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means. and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said step mechanism being selectively operable to halt movement of the carriage means in any one of several relatively shifted positions at'the work station to present a plate on said carriage means in adesired position at said station, a carrier for supporting theplate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward. and from said station, and means to support the carrier and plate in any selected one of a plurality of transversely shifted positions on the carriage means.

6. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the, carriage meansand on said frame means, said stop mechanism being selectively operable tohalt movement of the carriage means in any one of several relatively shifted positions at the work station to present a plate on said carriage means in a desired position at said station, progressively operable means to adjust the selectively operable stop mechanism during successive working cycles of the carriage means, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, actuating means to so move the carrier progressively from one transversely shifted position to another, and means selectively conditionable to cause the actuating means to operate and to remain inoperative during successive working cycles of the carriage means. i

'7. Plate positioning mechanism comprising frame means forming a work station, carriage means movableto and retractable from the work station in a working cycle, a carrier for supporting the plate on said carriage meanssaid car.- rier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, actuating means to so move the carrier progressively from one transversely shifted position to another, and means selectively conditionable to cause the actuating means to operate and to remain inoperative during successive working cycles of the carriage means.

8. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movement of the carriage means in anyone of several relatively shifted positions at the work station to present a plate on said carriage means in a desired position at said station, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of. the carriage means toward and from said station, an electric motor on said carriage means, means for drivingly connecting the motor with said. carrier, comprising latch means normally operable to latch the carrier against movement and releasable to allow the carrier to be moved by motor, and latch control means selectively conditionable to cause relatching of the carrier after thesame has been shifted a predetermined distance on the carrier means.

9. Plate conditioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movement of, the carriage means in any one of several relatively shifted positions at the Work station to present a plate on said carriage means in a desired position ,at

said station, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, an electric motor on said carriage means, means for drivingly connecting the motor with said carrier, comprising latch means normally operable to latch the carrier against movement and releasable to allow the carrier to be moved by said motor, and latch control means selectively conditionable to cause relatching of the carrier after the same has been shifted a predetermined distance on the carriage means, said latch means comprising a plurality of latch portions operable to latch the carrier in any one of a plurality of relatively shifted positions and said latch control means comprising manually operable cam means conditionable selectively to disable certain of said latch portions while permitting others to function. l

10. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the Work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movementof the carriage means in any one of several relatively shifted positions at the work station to present a plate on said carriage means in a desired position at said station, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, an electric motor on said carriage means, means for drivingly connecting the motor with said carrier, comprising a slip clutch having a driven side connected to the carrier and a driving side connected to said motor, latch means normally operable to latch the carrier against movement and releasable to allow the carrier to be moved by said motor, latch control means selectively conditionable to cause relatching of the carrier after the same has been shifted a predetermined distance on the carrier means, and switch means for energizing the motor upon release of said latch means and for disabling the motor upon relatchment thereof.

11. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movement of the carriage means in any one of several relatively shifted positions at the work station to present a plate on said carriage means in a desired position at said station, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, an electric motoron said carriage means, means for drivingly connecting the motor with said carrier, comprising a slip clutch having a driven side connected to the carrier and a driving side connected to said motor, latch means normally operable to latch the carrier against movement and releasable to allow the carrier to be moved by said motor, latch control means selectively conditionable to cause relatching of the carrier after the same has been shifted a predetermined distance on the carrier means, and switch means for energizing the motor upon release of said latch means and to disable the motor upon relatchment thereof, said latch means comprising a plurality of latch portions operable to latch the carrier in any one of a plurality of relatively shifted positions and said latch control means comprising manually operable cam means conditionable selectively for disabling certain of said latch portions while permitting others, to function. I

12. Plate positioning mechanism comprising frame means forming a work station, plate carriage means movable to and retractable from the work station to provide a working cycle, said frame means and carriage means comprising relatively movable structures, cooperating stop mechanism on the carriage means and on said frame means, said stop mechanism being selectively operable to halt movement of the carriage means in any one of several relatively shifted positions at the work station to preserita plate on said carriage means in a desired position at said station, a carrier for supporting the plate on said carriage means, said carrier being movable on the carriage means in a direction transverse with respect to the movement of the carriage means toward and from said station, an electric motor on said carriage means, means for drivingly connecting the motor with said carrier,

comprising a slip clutch having a driven side'- connected to the carrier and a driving side con-' nected to said motor, latch means normally operable to latch the carrier against movement and releasable to allow the carrier to-be moved by said motor, latch control means selectively conditionable to cause relatching of the-carrier after the same has been shifted a predetermined distance on the carrier means, switch means'for energizing the motor upon release of said latch.

means and for disabling the motor upon relatchment thereof, said latch means comprising a plurality of latch portions operable to latch the carrier in any one of a plurality of relatively shifted positions and said latch control means comprising manually operable cam means conditionable selectively to disable certain of said latch portions while permitting others to function by the engagement of said stop member with the co operating stop, means to drive said shiftable stop from said motor through said clutch under the control of said latch means, said cooperating stop being adjustably movable, switch means controlled by said manually operable means for controlling the movement of said cooperating stop, and switch means controlledby said manually operable means for controlling the operation of said motor. V

ARTHUR J. KIZAUR. 

